The stems of Plectroniella armata are covered in a rusty brown bark that is initially smooth, becoming grey and roughly fissured with age. Sturdy, straight spines of up to 4 cm long arm the stems in opposite pairs, growing slightly at an angle. The spines may disappear from large stems.
The flowers of this tree appear on spur-branchlets from leaf axils in dense corymbs of about 4 cm in diameter. They are creamy white, bell-shaped with the corolla lobes recurving over the tube and the throat hairy. Each flower has a three-lobed, protruding stigma. The tree flowers in spring and summer.
Plectroniella is a monotypic genus (one species only) that has from molecular studies been found to be related to the Canthium genus and may be moved there. That would bring the common name of false turkey-berry up for review as the tree would find itself among the proper turkey-berries (Coates Palgrave, 2002; Van Wyk and Van Wyk, 1997).